Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfb83b8e289bbecf…

MALICIOUS

PDF

80.5 KB Created: 2021-09-13 04:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ee4c01f02450b4928cf979a9ab4724aa SHA-1: 9448ea4ec1cb51a8abc1d01f7cc356dad7ced921 SHA-256: bfb83b8e289bbecf3b8c87dec6e0a5d75b221416bdf6e6925a7e72de8f89afdf
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many of which point to PDF files hosted on potentially compromised websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://betalinktech.com/blmedia/file/64943025910.pdf In PDF document text
    • http://grandrosso.com/js/upload/files/71777797359.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/temedesufupik.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/71185873205.pdfIn PDF document text
    • http://sarljarry.com/userfiles/file/parudi.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a9db1ec3b---4868908361.pdfIn PDF document text
    • https://phr4u.com/files/31873280734.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/37371368957.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/aa53b6f946c3b615f3c8f437def38504/gogag.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/456f20373c18bdf9065788a34d85ed6e/37623218141.pdfIn PDF document text
    • http://suphammamnon.org/uploads/files/24168051830.pdfIn PDF document text
    • http://anninh247.info/upload/files/8930844750.pdfIn PDF document text
    • http://info56.ru/userfiles/file/wujokudifirokewoxonuzatap.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/22212653246.pdfIn PDF document text
    • https://www.netcorp.hu/data/editorfile/43145634336.pdfIn PDF document text
    • http://15881588.com/ckupload/files/supafawu.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/vulilavivinigobuxujurire.pdfIn PDF document text
    • https://immobiliareincentro.it/allegati/file/18147218588.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/jekukokibokazerinil.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/ludelefowoxot.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/jofuripojukezo.pdfIn PDF document text
    • https://firmabudowlanawalczak.pl/web/uploads/files/vabemupiwovodolow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=apk+galaxy+storePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d513.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD513 10520 bytes
SHA-256: f4a92d0ae91a20498e956b1b1e3949cb7506f5cc0347d7d5d02b365d17551b1f
font_01_sfnt_off0000ed4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4C 18084 bytes
SHA-256: 764e355c8aac6cba1271535bc79a3f6de83fc66507fccfeae638856063c39c7b
font_02_sfnt_off00011ca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1